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            <h2 class="title" style="clear: both"><a id="dbprops"></a>Database Properties</h2>
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      <p>You can set database properties using the <code class="classname">DatabaseConfig</code>
    class. For each of the properties that you can set, there is a
    corresponding getter method. Also, you can always retrieve the
    <code class="classname">DatabaseConfig</code> object used by your database using
    the <code class="methodname">Database.getConfig()</code> method.</p>
      <p>The database properties that you can set are:</p>
      <div class="itemizedlist">
        <ul type="disc">
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setAllowCreate()</code>
            </p>
            <p>If <code class="literal">true</code>, the database is created when it is
        opened. If false, the database open fails if the database does not
        exist. This property has no meaning if the database currently exists.
        Default is <code class="literal">false</code>.</p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setBtreeComparator()</code>
            </p>
            <p>Sets the class that is used to compare the keys found on two
        database records. This class is used to determine the sort order for
        two records in the database. By default, byte for byte comparison is
        used.
        For more information, see 
        <span><a class="xref" href="comparator.html" title="Using Comparators">Using Comparators</a>.</span>
        
        </p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setDuplicateComparator()</code>
            </p>
            <p>
            Sets the class that is used to compare two duplicate records in
            the database.  For more information, see 
            <span><a class="xref" href="comparator.html" title="Using Comparators">Using Comparators</a>.</span>
            
        </p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setSortedDuplicates()</code>
            </p>
            <p>If <code class="literal">true</code>, duplicate records are allowed in the
        database.  If this value is <code class="literal">false</code>, then putting a duplicate record into the database
        results in an error return from the put call.
        Note that this property can be set only at database creation time. Default is <code class="literal">false</code>. 
        </p>
            <p>
            Note that your database must not support duplicates if it is to be associated with one or more 
            secondary indices. Secondaries are described in <a class="xref" href="indexes.html" title="Chapter 10. Secondary Databases">Secondary Databases</a>.
        </p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setExclusiveCreate()</code>
            </p>
            <p>If <code class="literal">true</code>, the database open fails if the
        database currently exists. That is, the open must result in the
        creation of a new database. Default is <code class="literal">false</code>.</p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setReadOnly()</code>
            </p>
            <p>If true, the database is opened for read activities only.
        Default is <code class="literal">false</code>.</p>
          </li>
          <li>
            <p>
              <code class="methodname">DatabaseConfig.setTransactional()</code>
            </p>
            <p>If true, the database supports transactions.
        Default is <code class="literal">false</code>. Note that a database cannot support
        transactions if the environment is non-transactional.</p>
          </li>
        </ul>
      </div>
      <p>For example:</p>
      <a id="je_db3"></a>
      <pre class="programlisting">package je.gettingStarted;

import com.sleepycat.je.DatabaseException;
import com.sleepycat.je.Database;
import com.sleepycat.je.DatabaseConfig;

...
// Environment open omitted for brevity
...

Database myDatabase = null;
try {
    DatabaseConfig dbConfig = new DatabaseConfig();
    dbConfig.setAllowCreate(true);
    dbConfig.setSortedDuplicates(true);
    myDatabase = 
        myDbEnv.openDatabase(null, 
                             "sampleDatabase", 
                             dbConfig); 
} catch (DatabaseException dbe) {
    // Exception handling goes here.
}</pre>
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